1. Field of the Invention
The invention relates to a unit for automatic container returns systems, e.g. for cans and bottles made of glass, plastic or metal, in which the containers are transported in the horizontal position by a conveyor device to an identification station in which the characteristic data of the containers is ascertained and in which the further treatment of the containers is determined, e.g. whether they are to be rejected for removal from the conveyor device or, if appropriate, transported to another unit.
2. Description of the Prior Art
A unit for automatic container returns systems is known from WO 98/02853. In this the conveyor device comprises a group of parallel belts spanning between two pulleys. Said belts form a diabolo shape in cross-section so that the group of belts forms a V-shaped configuration on the top in which the container to be conveyed is located. A roller extending roughly the length of the conveyer path is positioned on both sides and alongside the conveyor path, with each roller being attached to the end of a pivoting lever. The rollers are equipped with a drive to rotate them and by means of a pivoting movement are moved towards each other and into contact with the container at the identification station, thereby lifting said container and simultaneously causing it to rotate so that specific data, e.g. in the form of a barcode, on the outside of the container and rotating with the container can be detected by an identification unit, even when it was previously not in the xe2x80x9cfield of viewxe2x80x9d of the identification unit. In doing so, depending on the result of the identification process, a decision is made as to what should happen to the container next, e.g. whether it is to be rejected sideways from the conveyor device, or whether it is to be transported to the next unit in order to be compacted or treated in some other way there. In the known unit a pivoting mechanism driven by a motor is provided above the conveyor device for the sideways ejection, whereby said mechanism grips the container transported on the conveyor device and pushes this out of the conveyor device, if necessary by way of a pivoting movement to one side or the other.
The invention is based on a unit for automatic container returns systems with a conveyor device for transporting the containers in the direction of their longitudinal axis, two rotary-driven rollers arranged along the conveyor path, which can be transferred from a neutral position into an identification position in which they release the container from the conveyor device and rotate said container, and a sorting means for the selective, lateral removal of the container from the conveyor device depending on the identification.
It is the object of the invention to provide a generic unit for automatic container returns systems that is characterised by a simple construction.
This object is achieved with the generic unit according to the invention in that the two rollers act as a sorting means by way of their being transferred transverse to the conveyor path into a sorting position in which the lateral distance between one or other of the rollers and the conveyor path is so large that the container can drop down between the conveyor path and the respective roller displaced sideways.
The unit according to the invention has the advantage that no separate sorting device and its associated drive are required because the rollers provided for the identification function simultaneously carry out the sorting function.
In an advantageous arrangement of the invention it is the case that the conveyor device comprises two endless conveyor belts, each of which forms a common element with one of the rollers, that the conveyor belts simultaneously act as lateral guides for the containers transported on them when the rollers are in the neutral position, and that the elements consisting of roller and transport belt can be transferred into the sorting position.
In doing so it is the case that each conveyor belt passes over guide pulleys mounted in a frame, which is fitted such that it can rotate about the axis of the associated roller, and that the rotary drive for the rollers consists of a driven shaft positioned between said rollers, whereby the rollers are in contact with said shaft under a certain pretension. The advantage of this arrangement is that no form of drive needs to be provided in the rollers themselves.
To this end, each conveyor belt passes around guide pulleys positioned at the four corners of a rectangle and whose spacings relative to each other are such that the associated roller can project sideways by a prescribed dimension into the space enclosed by the conveyor belt. In another advantageous arrangement of this embodiment of the invention it is the case that the supports for the transport belts can be rotated from the neutral positionxe2x80x94in which the transport belts form a V-shaped channel for carrying the containerxe2x80x94about the axes of the rollers in opposing directions into the identification position so that the container is released from the transport belts and transferred onto the rotating rollers, and that the elements consisting of roller plus conveyor belt can be moved away from each other into the sorting position.
In a further advantageous arrangement of the invention it is the case that the conveyor device consists of a narrow endless conveyor belt, in which the rollersxe2x80x94when in the neutral positionxe2x80x94serve as lateral guides for the container being transported on the narrow conveyor belt.
In a practical arrangement of the invention it is the case that a driven shaft running in the conveying direction is provided between the upper strand of the conveyor belt and its lower strand, and that the rollers are fitted to the free ends of pivoting levers whose pivoting movement either moves the rollers towards each other from the neutral position into the identification position, in which they operate with the driven shaft, lift the container from the conveyor belt and rotate it, or away from the conveyor belt into the sorting position.
The advantage of this arrangement is that the rollers attached to the levers do not require their own drive.
In an advantageous arrangement of the invention it is the case that means are provided for pre-tensioning the levers carrying the rollers in the direction of the driven shaft, and releasable locking mechanism that holds the levers in a neutral position against the force of the means of pre-tensioning.
A form of drive is preferably assigned to the levers carrying the rollers through which the levers can be pivoted out of the sorting position against the force of the means of pre-tensioning if required. The form of drive here can consist of motors or solenoids.